THz-attenuated total reflection (THz-ATR) spectral detection technology for water-containing samples has the advantages of no labeling, no ionization and high detection sensitivity. It has great application potential in the qualitative and quantitative detection of disease markers, so it is of great practical significance for the early diagnosis and staged diagnosis and treatment of major diseases. On the basis of a brief introduction to the basic principles of THz-ATR technology for the detection of aqueous samples, the application of THz-ATR spectroscopy detection technology with different radiation sources in biomedical detection is analyzed and compared in detail. Finally, the research status and future development trend of THz-ATR spectral detection technology are briefly summarized.